The SPE Library contains thousands of papers, presentations, journal briefs and recorded webinars from the best minds in the Plastics Industry. Spanning almost two decades, this collection of published research and development work in polymer science and plastics technology is a wealth of knowledge and information for anyone involved in plastics.
|= Members Only|
Kinetics of Epoxy Curing in Composites Containing Glass Fibers or Glass Fibers Commingled with Polypropylene
Glass fibers used in this study are silane-treated woven glass mats and anhydride-treated polypropylene woven glass mats. The influence of these treatments on the epoxy resin curing kinetics is studied. Isothermal and dynamic kinetic parameters from Differential Scanning Calorimetry (DSC) are determined and compared. Based on enthalpies as a function of time results, the autocatalytic model is chosen for the analysis.
In-Line Investigation of Shear-Induced Morphology Transition in Liquid Crystalline Polymer/PET Blends
The morphology of a compatibilized polyethylene terephthlate and thermotropic liquid crystalline copolyester blend is investigated via in-line optical microscopy and light scattering. It was found that the droplet-fiber transition in the liquid crystalline polymer is dependent upon the reactivity, the viscosity ratio and the shear field. The fibers are strongly oriented along the flow direction. The formation, deformation and stability of fiber microstructure under different flow conditions are discussed.
Variation of the Self-Nucleation Domains in ABC Triblock Copolymers with Semicrystalline B and C Blocks
The self-nucleation behavior of the polyethylene (PE) block within polystyrene-block-poly(ethylene-co-butylene)-block-polycaprolactone triblock copolymers was investigated. The extent of self-nucleation was found to be highly dependent on the PE content of the copolymers. The self-nucleation was almost completely suppressed when the PE content was 15% by weight.
Thermogravimetric Analytical Techniques
Thermogravimetry (TG) is an important tool for materials characterization. Hyphenated and multihyphenated methods greatly enlarge the scope of TG. Some thirty different experimental approaches were identified, many with a proven record, but some new and promising but in need of confirmation, such as video-imaging-TG, flash-TG- MS and quench-TG. A review of the state of modern thermogravimetry is given.
TG-MS Family Tree
Strengths and weaknesses of thermogravimetry - mass spectrometry (TG-MS) in qualitative and quantitative industrial problem solving are outlined. The main features of the TG-MS hardware components are reported. Emphasis is laid on the great variety in design options, both for the TG, MS and interface components. The user's requirements for ideal TG-MS instrumentation are described and hyphenated TG-MS options are evaluated. HRTG-EI/SI QMS extended with a chemometrics software package is currently the most advanced option.
Mechanism of Organotin Stabilization of Poly(Vinyl Chloride). 3. the Structure and Equilibria of Alkyltin Alkyl Mercaptopropionates and Their Compatibility with PVC
A series of alkyltin 2-ethylhexyl mercaptopropionates was synthesized and their structure and equilibria with alkyltin 2-ethylhexyl thioglycolates and alkyltin chlorides studied by IR and 119Sn NMR. Compatibility with PVC was determined using DMA analysis of glass transition temperatures. The implications of these results on PVC stabilization are discussed.
Use of Non-Contact Scanning Technology as a Means to Reduce Product Development Lead times
The objective of this presentation is to discuss the implementation of a non-contact scanning inspection method that can reduce product development lead times by greatly reducing the time to qualify and/or quantify a product for production. The equipment, requirements, and methodology of this CAD based inspection method will be discussed. Additionally, case studies supporting this advanced inspection process will be presented.
Predicting Drop Breakup Using Model Flows
This work characterizes the deformation and breakup of a single drop subjected to a sudden onset shear flow. The drop is immersed in a second fluid with which it is immiscible. A cylindrical couette device is used to create simple shear flow on a time scale which is extremely short compared to the time scale of the deformation of the drop. Two breakup mechanisms were observed:elongative end pinching and capillary wave breakup.
Film Casting of a Low Density Polyethylene Melt
Film casting is one of the major commercial film manufacturing processes. Although various investigators have studied the process, no comprehensive set of data is available. In this study, film casting experiments of a LDPE polymer melt are conducted. The rheological properties of the melt, the film tension, the velocity profile, and the film width profile due to necking in will be presented. The thickness profile of the solidified film and the edge bead profile will also be reported. These experimental data will be useful for process analysis and verification of film casting simulation.
New Light Stabilizer for Coextruded Polycarbonate Sheet
Weatherable polycarbonate sheet can be produced by coextruding a cap layer containing a UV absorber over a minimally-stabilized bulk layer. A new UV absorber based on hydroxyphenyltriazine chemistry has been developed that is especially suited to this application. The product provides superior long term weatherability due to its strong UV absorbance and its excellent photostability. It is also relatively nonvolatile, and has only a minimal effect on melt viscosity.
Diffusion at Polymer-Polymer Interfaces Probed by ATR-Attenuated Total Reflection
In this work we report on the quantification of concentration profiles across the polystyrene-polyvinyl methyl ether interface through ATR-Attenuated total reflection technique. Different narrow molecular weight distributions and different temperatures above and below the glass transition temperature of polystyrene were tested both in the one phase and two-phase regions. The effects of temperature and molecular weight on the diffusion mechanism are discussed in terms of the phase behavior.
Determining Tear Resistance in Blown Film Using a Single Specimen J-Integral Approach
A single specimen J-integral approach is developed to determine the fracture toughness of thin polyethylene blown films. The test is used to determine the amount of energy required to initiate crack growth as well as the energy required to propagate the crack. This paper presents preliminary findings using the single specimen J-integral approach on LLDPE blown films. A comparison between J, Elmendorf, and Dart is provided.
Crack Growth Studies for Polyacetyl Resins in Chlorinated Water
The crack growth resistance in chlorinated water has been measured for two polyacetal resins of different molecular weights. The crack growth rates were measured using single edge notched tensile specimens under constant stress at elevated temperatures. The crack resistance measured in hot water containing free chlorine were found to provide a reasonable explanation for the observed poor field performance of these resins in hot water plumbing applications.
Fluorescence Anisotropy Measurements of Oriented Polymers
Fluorescence anisotropy area scans of sheet and film specimens have been carried out using a fiber optic sensor that contains polarizing optical elements. Measurements on polyethylene terephthalate food packaging, which contains the fluorescent dye benzoxazolyl stilbene, are presented. In one case, a sheet cut from the side of a blow molded bottle displayed variation in biaxial orientation as a function of distance from the neck of the bottle. In another case, a thin film of shrink wrap material showed uniform biaxial orientation over the scanned area.
A Quantitative Investigation of Mixing in a Miscible SAN/PMMA Blend
Mixing of miscible additives into polymeric matrices is being investigated using the model blend SAN/PMMA. The normalized sample variance, as measured by FT-IR, is used to quantify the extent of mixing. The graph of normalized sample variance as a function of sample size reveals that there are at least two characteristic size scales present in short-time mixing samples. Theoretical calculations support this conclusion.
Three Dimensional, Nonisothermal Analysis of RTM and VARTM Processes Using hp-Adaptive Finite Element Method
A highly accurate numerical technique for the simulation of resin infusion in composite preforms using a transient, 3-D, non-isothermal, two-phase analysis is presented. An adaptive finite element method is used to solve the equations. The uniqueness of the present approach is that resin infusion is modeled as a weakly compressible, two-phase flow in a porous media. VARTM processes can be solved by accurately specifying air properties based on the vacuum conditions. The results presented indicate the usefulness of the model.
Solvent Effects on the Mechanical Properties of Peek: An In-Situ Dynamic Mechanical Analysis Technique
Amorphous poly(ether ether ketone)(PEEK) plasticizes and/or crystallizes in the presence of common organic solvents. In-situ Dynamic Mechanical Analysis techniques have been employed to study the effects of solvent-induced crystallization on the storage modulus (stiffness) of amorphous PEEK. Preliminary results indicate that the Tg of PEEK is depressed below 20°C allowing for room temperature crystallization. Real-time immersion at room temperature shows the competing effects of plasticization and crystallization on the mechanical response of PEEK.
Cavity Pressure Studies for Stereolithography Produced Tooling
The objectives of the study are to: 1)Determine the relationship between cavity pressure and tool failure; 2)Evaluate the feasibility and effectiveness of cavity pressure transfer from first to second stage for stereolithography (SLA) produced tooling; and 3)Evaluate the effectiveness of computer simulation in determining the startup conditions for the AIM* injection molding process.
Investigation of the Reaction Kinetics within Expandable Mixtures Used for Preparing Injection-Molded Polyolefin Foams
In this study, expandable polyolefin elastomer mixtures used for preparing cross-linked polyolefin foams were studied by Differential Scanning Calorimetry (DSC) to determine the reaction rate constants for azodicarbonamide (AZDC) decomposition. Activation energies and rate constants were computed from results obtained by variable heating rate DSC experiments. Predictions made from the kinetic equations were compared with results from isothermal aging experiments as well as observations made during injection molding of cross-linked foams.
Effect of Applied External Pressure on the Surface Concentration of Erucamide in LLDPE Films
External pressure was applied to extruded LLDPE films with an average thickness of 70 microns at 35°C and 50°C for prescribed periods of time. The final surface concentration of the slip agent (erucamide) was then compared to the initial concentration. Three applied pressures were used and diffusion profiles were determined using FTIR-ATR spectroscopy.
We're sorry, but your current web site security status does not grant you access to the resource you are attempting to view.
Any article that is cited in another manuscript or other work is required to use the correct reference style. Below is an example of the reference style for SPE articles:
Brown, H. L. and Jones, D. H. 2016, May.
"Insert title of paper here in quotes,"
ANTEC 2016 - Indianapolis, Indiana, USA May 23-25, 2016. [On-line].
Society of Plastics Engineers
Note: if there are more than three authors you may use the first author's name and et al. EG Brown, H. L. et al.
If you need help with citations, visit www.citationmachine.net